Embodiments of the present invention relate generally to cold-cathode switching devices. Particularly, an embodiment of the present invention relates to cold-cathode switching devices suitable for use in high-voltage power conversion applications.
Semiconductor switches are widely used in high-voltage power conversion systems because of their reliability and long life. However, the open-circuit standoff voltage of each semiconductor switch is relatively low (for example, about 10 kV), such that many semiconductor switches have to be stacked together in series to handle the high voltages (300-1000 kV). Further, the cost and complexity of the high-voltage power conversion systems employing semiconductors switches may be undesirably high.
Gas switches can stand off higher voltages for example, greater than 100 kV. However, gas switches are not widely used, because their reliability and life are not sufficient for use in electric grid applications. Low reliability and short life arise in part from damage to the cathode surface caused by ion bombardment, sputtering, heating, and evaporation during switch operation.
Accordingly, there is a need for improved gas switch configurations. Further, it may be desirable to have reliable gas switch configurations that may be used in high-voltage power conversion applications.